#ifndef _TOKEN_H_
#define _TOKEN_H_

struct inode{
    int ival;
    int iop; //0:add, 1:minus, 2:mul, 3:div
    inode* left;
    inode* right;
};

inode* create_node(int val, void*left, void*right, int op);

void set_root(void*);
void mid_tra(inode*tmp_ptr);

#endif